Hi Victoria,
These words are synonymous! That means they are the same thing!
But to be sure, here are the two definitions from dictionary.com:
Source:
1. any thing or place from which something comes, arises, or is obtained; origin: Which foods are sources of calcium?
2. the beginning or place of origin of a stream or river.
3. a book, statement, person, etc., supplying information.
4. the person or business making interest or dividend payments.
5. a manufacturer or supplier.
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Origin:
1. something from which anything arises or is derived; source; fountainhead: to follow a stream to its origin.
2. rise or derivation from a particular source: the origin of a word.
3. the first stage of existence; beginning: the origin of Quakerism in America.
4. ancestry; parentage; extraction: to be of Scottish origin.
5. Anatomy .
a. the point of derivation.
b. the more fixed portion of a muscle.